An IP address ending in .0 is perfectly legal these days. However, some devices (and firewall policies) believe that it isn't.
In the old "classfull" addressing scheme, IPs from 192.0.0.0 to 223.255.255.255 were considered "class C" space, i.e. they had an implicit subnet mask of 255.255.255.0.
So, back then, you couldn't actually have a .0 host address, because .0 was the "network address". Similarly you couldn't have a .255 address within that range because that was the broadcast address.
About 20 years ago, though, everyone changed to "classless" CIDR style addressing, with variable length subnet masks, and no implicit subnet masks. If you've got a /23 then there shouldn't be any reason why you can't use the .255 that's at the end of the first /24 and the .0 that's at the start of the next.
However, 5+ years ago when I was in the ISP industry our system would happily give out .0 and .255 addresses to end users, but then we found that they couldn't reach Microsoft's websites because they had either broken kit, or overzealous firewall rules. We ended up having to exclude those addresses, even though they're legal.
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